低强度微波对烟草叶片细胞膜系统和POD同工酶的非热效应

Non-Thermal Effect of Microwave on Membrane System of Cell and Peroxidase Isoenzymes in Leaf of Tobacco

在300MHz低强度微波辐射下,烟草叶片细胞膜电解质渗漏率增加,膜脂过氧化产物丙二醛(MDA)含量增加,超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性降低,表明微波抑制了细胞膜保护酶系统的活性,使膜脂产生了过氧化作用。进一步的研究表明,烟草类囊体膜膜脂不饱和度指数(index of unsaturated fatty ac id,IUFA)下降,膜流动性减小,类囊体膜结合酶Ca2+-ATP酶和Mg2+-ATP酶活性升高。低强度微波还使烟草叶片过氧化物酶(POD)活性发生了变化,电泳分析显示,POD同工酶谱的染色和条带都有所改变。烟草叶片细胞发生的这些变化是微波对光合细胞的一种非热效应。

Under the 300MHz low level microwave radiation, the relative electric conductivity of cell membrane and the content of malonadialehyde （MDA） in leaf of tobacco were increased, the activities of superoxide dismutase （SOD） and catalase（CAT） were decreased. These results indicated that microwave made membrane lipid peroxidation and the damage of membrane of the cell in leaf of tobacco. Further study showed that the fatty acid composition of thylakoid membrane in cell of tobacco leaf changed. Compared with control experiment, index of unsaturated fatty acid （ IUFA ） and the fluidity of thylakoid membrane were reduced, the activities of Ca^2 ＋ - ATPase and Mg^2＋ - ATPase on thylakoid membrane were increased under the radiation of microwave. Microwave made the activity of peroxidase（POD） in leaf of tobacco changed also. The detection of peroxidase isoenzymes pattern indicated this change. The changes of photosynthesis cell membrane system in leaf and peroxidase isoenzymes pattern in cell were non - thermal effects of microwave on photosynthesis cell of plant.